Final answer:
Dwight D. Eisenhower was the president who created the interstate highway system in 1956 with the passage of the Federal Aid Highway Act, ushering in a new era of high-speed roadways that significantly influenced American suburbanization and transportation.
Step-by-step explanation:
The president who created the interstate highway system was Dwight D. Eisenhower. In 1956, under Eisenhower's presidency, Congress passed the Federal Aid Highway Act. This act was influenced by the inadequacy of the existing road network for military movements, as seen in a convoy test in 1919 and Eisenhower's observations of the German Autobahn during World War II. The result was the establishment of a national network of high-speed roadways, intended not only for military use but also for civilian purposes, greatly enhancing suburbanization and changing the urban landscape. Automobile and oil companies were among the strongest supporters of the act, while it raised concerns for small businesses that were bypassed by the new roads.